For the yeast dough muffins with chocolate chips, mix flour, dry yeast, salt, powdered sugar. Heat the milk and butter and knead with the egg yolks to a dough.
Knead in chocolate chips. Let dough rise for about 1 hour.
Butter muffin tins and fill with dough (approx. 12 muffins). Let rise again for about 15 minutes.
Bake the yeast dough muffins with chocolate chips at 190°C for about 20 minutes.